Floor structure for cargo container

ABSTRACT

A floor structure for a cargo container comprises a plurality of spaced apart and parallel channel members extending between longitudinal side members. The channel members are interconnected by metal plate members to form a rigid pallet like structure having transverse pockets to receive the forks of a lifting type freight vehicle.

United States Patent [191 Dougherty Oct. 7, 1975 FLOOR STRUCTURE FOR CARGO CONTAINER [76] Inventor: Robert Dougherty, Upper Ames Ave., Ross, Calif. 94957 22 Filed: Dec. 3, 1973 21 Appl. No.: 420,800

[52] US. Cl. 220/1.5; 220/72; 220/74; 220/DIG. 2S; 220/DIG. 29 [51] Int. Cl. B65D 87/00; B65D 7/42 [58] Field of Search 220/l.5, 71, 72, DIG. 25, 220/DIG. 29, 83, 84, 67, 70, 74; 52/177, 471, 495, 579

[56] References Cited UNITED STATES PATENTS 689,735 12/1901 Meehan 220/72 1,224,052 4/1917 Worth 52/495 Shanor.. 220/72 Focht 52/579 I 2,773,718 12/1956 Bohlen 52/579 2,910,322 10/1959 Magor 220/72 3,085,707 4/1963 Tantlinger 220/l.5 3,599,823 8/1971 Morris et a1 220/4 F FOREIGN PATENTS OR APPLICATIONS 52,982 7/1942 Netherlands 52/495 Primary ExaminerWilliam 1. Price Assistant ExaminerJoseph M. Moy

Attorney, Agent, or Firm-Owen, Wickersham & Erickson [57] ABSTRACT A floor structure for a cargo container comprises a plurality of spaced apart and parallel channel members extending between longitudinal side members. The channel members are interconnected by metal plate members to form a rigid pallet like structure having transverse pockets to receive the forks of a lifting type freight vehicle.

6 Claims, 13 Drawing Figures I I I I I I I US. Patent Oct. 7,1975 Sheet 1 of2 3,910,446

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US. Patent Oct. 7,1975 Sheet 2 of2 3,910,446

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FLOOR STRUCTURE FOR CARGO CONTAINER BACKGROUND OF THE INVENTION This invention relates to cargo or shipping containers for use in transporting freight on ships, trains, trucks and other transport means and more particularly it relates to a unique floor construction for such containers.

Cargo containers of the aforesaid type have been used to an increasingly greater degree because they substantially increase the speed, convenience and efficiency of freight handling, prevent pilferage and reduce overall freight costs. The size and capacity of such containers is standardized and controlled by domestic and international regulations andagreements so that they can be readily stowed on container ships and loaded on various types of land transport vehicles such as trains and trucks. However, the precise construction of such containers has not been standardized and considerable efforts have been made heretofore to provide the most advantageous construction. It is essential that the containers be strong and durable, and yet they must be as light as possible and therefore capable of being readily lifted and moved by such freight handling equipment as fork lift trucks. Heretofore, the most common form of freight container was the so-called FRP type, that is one utilizing a fibreglass-reinforced-plywood panel attached to frame members. In such containers the floor was generally comprised of metal frame members covered by wood planks or sheets. In order for such a floor construction to fulfill the desired strength requirements, a considerable amount of material and labor was necessary. Also, because of increasing shortages of lumber and its consequent high price, coupled with the problems of sealing the floor against moisture and infestations by insects, a need for a suitable allmetal floor arose. The problem was to provide such a floor construction having sufficient strength and yet light in weightand also one that is compatible with various standard fabrication techniques for the walls of the container. It is therefore a general object of the present invention to provide a freight container with an improved all-metal floor construction that solves the aforesaid problems. g

Other important objects of the present invention are to provide an all metal floor construction for a freight container that has a relatively high strength to weight ratio to provide a floor construction that will enable the container to be readily lifted and m aneuvered-byfork lift trucks and the like to provide a floor construction for freight containers that is strong and durable and to provide a container floor construction that is particularly well adapted for ease and economy of manufacture.

SUMMARY OF THE INVENTION In general, a container floor construction according to the present invention is comprised of a series of metal channel members arranged in a spaced apart, parallel order to form the Width of a rectangular-shaped container floor. The ends of these channel members are connected to a pair of opposite, parallel side members. The web portion of each channel member is provided with a series of elongated spaced apart; trans longitudinal shoulder or offset forming a narrowledge. Extending between adjacent spaced apart pairs of channel members are elongated metal plates whose opposite side edge portions are supported within the aforesaid longitudinal ledges of the channel members. These plate strips are also provided with spaced apart, transverse stiffening recesses along their. length. The edge of each plate strip is welded to the shoulder of the channel member forming its edge depression- When fully assembled the web portion of channel members and the plate strips between them as joined together form a pallet-like platform or container floor that is essentially smooth on its upper surface except for the recesses and substantially flush fasteners or weldments. Side, end and top wall members of any suitable construction are then added to the floor structure to form a completed container.

Other objects, advantages and features of my invention will become apparent from the following detailed description taken with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in perspective of a shipping container having a floor construction embodying the principles of the present invention and shown as it is being manipulated by a fork-lift truck;

FIG. 2 is an end view in elevation of the container of FIG. 1;

FIG. 3 is a side view in elevation of a container of FIG. 1;

FIG. 4 is a plan view of a container floor structure according to the present invention;

FIG. 5 is a view in elevation and in section showing a single line representation of my floor taken at line 5-5 of FIG. 4;

FIGS. 6 and 7 are enlarged fragmentary views taken at lines 6 and.7 respectively of FIG. 4;

DETAILED DESCRIPTION OF PREFERRED i EMBODIMENT With reference tothe drawing, FIGS. 1-3 show a completed cargo container 20 for storing freight for transport on various types, of vehicles and having a floor structure 22 according to the present invention.

FIG. l'illustrates how the container may be maneuvered forloading and unloading it on a transport vehicle by means of a typical fork-lift truck 24. The container floor has a series of four elongated openings 26 which extend transverse to its longitudinal dimension and are spaced apart along its sides to receive the forks of the lift-truck. Attached to and extending vertically upward from the sides and ends of the floor are pairs of sidewalls 28 and endwalls 30, at least one of the latter having hinged access doors 32. These walls are connected at :their top edges to a suitable roof structure which completes the enclosure around the floor. The sidewalls, endwalls, roof and access door may be con- FIG. 8 is a view in section taken at line 8-8 of FIG.

strueted in any suitable manner which is compatible with my floor structure. The particular'w all structure illustrated is of "the metal frame and corrugated metal type, but a standard metal frame and fibreglass reinforced panel (FRP) type of structure could also be used with my floor structure22, which provides the basic platform for the'container. Since the structural details of the alternative wall constructions are well known to those skilled in the art, they will not be described in detail herein.

As shown in FIGS. 4 and 5, my floor structure 22 generally comprises a seriesof spaced apart, relatively stiff, metal cross members 38 formed with predetermined cross' sectional shapes and connected to somewhat less rigid, substantially flat plate members- 40 lo-' cated betweenthe stiffer members. In the embodiment shown, most of the stiffer cross members 38 have a channel-like cross sectional shape with a central web portion 42, downwardly extending side flanges 44 and inwardly extending flanges 46 on the lower edges of the side flanges. Preferably, these cross members are formed by bending sheet steel into the desired channel shape, but other forming means or other kinds of metal could be used within the scope of the invention. As shown in FIG. 9, the central web portion 42 of each channel cross member 38 is formedwith an elongated shoulder 48 spaced inwardly from each junction of the web and a side flange. This forms a pair of narrow ledges 50 near the opposite edgesof each web portion, each being lower from the surface of the web portion by a distance approximately equal to the material thickness of the adjoining plate member 40 (e.g. ll gauge sheet steel). When 'my'floor is assembled, as shown best in FIGS. 4 and 8, the channel cross members 38 are arranged at parallel, spaced apart intervals.

The'sheet metal plate members 40 are located between them with their opposite edge portions resting in the elongated ledges 50 of the web portions 42 of adjacent channel members, as shown in FIG. 9. Each plate member 40 is attached to a channel member by welding,

preferablyby providing an elongated weldment 52 that joinsthe edge of the plate to the shoulder 48 of the adjacent channel member. i

In order to adjust the length and reduce the weight of the floor I may vary the width of the members 38 and and I may also use-cross members 54 having a right angle cross section instead of a channel cross section. Such across member has a horizontal flange portion and one downwardly extending flange portion 56 with an inwardly extending lower edge flange 58 as on the channel cross member. Here, as shown in FIG. 4, the edge of the horizontal flange portion of this cross mem-- ber 54 is fixed to an-adjacentchannel member 38 in the same manner as a plate member 40, while the other side'of the web portion is fixed tothe edge of another plate member. Thus, it is seen in FIGS. 4 and 5, the relatively stiffer channel and the right angle cross mem-,

bers 38 and 54 combined with thealternate plate members 40, when welded together, form a strong, rigid platform surface which is also relatively lightweight.

' Spaced apart at even intervals along the web portions 42 of each of the various cross members'38 and 54 and transverse to its longitudinal dimension are a series of parallel elongated recesses or depressions 60. (See FIGS; 4 and 7). Similar recesses or depressions 62'are provided in the plate members 40, as shown in FIGS.

stamping method in 'th'e various members before the floor is assembled to a depth of about one half their width (e.g. a depth of around Va inch for l 1 gauge sheet steel). They provide increased stiffness to both the cross members and plate members without increasing weight". Yet, the recesses are sufficiently narrow and are spaced far enough apart so that they have no effect on the wheels of standard freight handling vehicles and apparatus. Therefore, to such vehicles the floor upper surface is substantially flat and has no obstructions which couldinterfere with the operation of such freight handling equipment within a container.

Along the sides of the floor 22 the end edges of the cross members 38 and plate members40 are aligned and are welded to a pair of opposite side frame'members 64, as shown in FIGS. 4 and 11. These side members, preferably formed from the same durable material as the other floor components such as sheet steel, have an upper portion with a channel shaped cross section formed by a vertical web 66 having inwardly extending having a similar cross section to the side members 64.

Preferably, this member has a shoulder 78 in the, lower flange of its upper channel portion which forms an elongated ledge 80 for the edge of anend plate member 404 as shown infFlG. 12. An elongated weldment 82 maybe used to secure this edge of the end plate member to the shoulder 78. The end member 76 extendsbetweenand is attached to two vertical frame members 84 of the endwall 30-which are connected at their top by an upper horizontal frame member 86. As stated above, these frame members are adapted to support a suitable wall siding such as corrugated sheet metal 88 or fibreglass-reinforced plywood panels.

At the other end of the container, as shown in FIGS. 4 and 10, an end plate member 40!) isconnected, as by welding, to a lower frame member 90 of the other end wall which is equipped with standard freight container doors 32. Since these latter doors are of standard construction and are available commercially they need not be described in detail. Here. the top surface of the lower frame member which has a rectangular cross sec tion, is flush with the adjoining floor plate so that a freight handling vehicle can roll through the doors 32 into the container with no obstruction when the doors 1 As stated above, suitablesiding such as corrugated metal or prefabricated panels may be used to form the container walls between the vertical frame members.

For supporting the container roof, upper horizontal side members 96 are provided between the vertical end .framemembers 84 and 92, and these upper side mem- 4 and 6. All of these recesses are formed by a cold berssupport a suitable roof paneling. The fabrication they are not part of the invention and any suitable standard construction can be used. My unique floor structure 22 can provide the basic platform for a container using various types of wall or paneling materials.

For purposes of illustration the walls of the container are shown using corrugated sheet metal. .As shown in FIGS. 3 and 13 where corrugated metal 88 is used for the sidewalls, its lower end edge is flush against and attached to the upper flange 68 of the channel portion on each side member 64. At spaced apart intervals along this upper flange a series of slots or holes 98 are provided which serve tie down means for strapping or nailing, used in securing freight within the container.

As shown in FIG. 3, the four access openings or pockets 26 for the forks of a loading vehicle are cut in the vertical flange 72 of the side members 64 of the container floor structure. These Openings are spaced between channel cross members 38 of the floor structure. The two innermost openings are spaced apart the standard distance between lifting forks of a typical freight vehicle. The outermost openings are located to align with other spaces of the floor structure formed between other cross members and they are spaced farther so as to equal an extended distance between the fork members of freight handling vehicles.

When a container having the floor structure 22 according to the present invention is maneuvered by a freight handling vehicle 24, as shown in FIG. 1, the forks of the vehicle may be inserted into the two innermost openings 26 of the floor if the container is lightly loaded or empty. When the container is filled and much heavier, the forks of the freight handlingvehicleare used in the outermost openings 26. In either case the structural integrity of the cross member and welded plate arrangement of my floor structure provides a high degree of strength and rigidity with a minimum of weight. The advantage of the latter is extremely important since in all freight operations, weight and cost are directly related.

To those skilled in the art to which this invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the spirit and scope of the invention. For example, although my floor structure has been described with particular reference to cargo containers it should be apparent that it is also applicable to and useful on other structures, such as the van portion of truck trailers.

l claim:

1. In a portable cargo carrying container for use in storing and transporting freight, a metal floor structure for said container comprising,

a rigid rectangular metal frame member including side and end rails,

a plurality of elongated relatively stiff metal .Crossmembers laterally spaced apart at intervals along the length of said side rails,

said cross-members each provided with a web por tion having its marginal side edge portions depressed below its top level by a predetermined amount, wall depending from each depressed side edge of the web portion, plurality of elongated metal plate members, each located between a pair of adjacent spaced apart cross-members and welded at its side edges to the depressed marginal edge portions of the web portions, the thickness of said plate members being substantially equal to the amount by which the marginal side edge portion of a web portion is depressed,

said side rails each including a vertical wall,

the end edges of said plate members of said web members and of the depending walls of the web portion abutting the vertical wall and being welded thereto, to secure said plate members, crossmembers and side rails together into a unitary selfcontained structure free of external fastening devices and/or overlapping portions of materials.

2. In a portable cargo carrying container according to claim 1 wherein the depending wall of at least one side rail is provided centrally of its ends with at least one pair of longitudinally spaced openings for receiving the lifting forks of a freight-handling vehicle, each opening registering with the space between a pair of adjacent cross-members beneath an intervening plate member.

3. In a portable cargo carrying container according to claim 2 wherein the depending walls from each cross-member terminates at their free ends with inwardly turned flanges extending toward one another.

4. In a portable cargo carrying container according to claim 1 wherein the depending walls from each cross-member terminates at their free end with inwardly turned flanges extending toward one another.

5. In a portable cargo carrying container according to claim 1 wherein the plate members and web portions are provided with transversely extending evenly spaced stiffening indentations along the lengths thereof.

6. In a portable cargo carrying container according to claim 1 wherein the plate members and web portions are provided with transversely extending evenly spaced stiffening indentations along the lengths thereof. 

1. In a portable cargo carrying container for use in storing and transporting freight, a metal floor structure for said container comprising, a rigid rectangular metal frame member including side and end rails, a plurality of elongated relatively stiff metal cross-members laterally spaced apart at intervals along the length of said side rails, said cross-members each provided with a web portion having its marginal side edge portions depressed below its top level by a predetermined amount, a wall depending from each depressed side edge of the web portion, a plurality of elongated metal plate members, each located between a pair of adjacent spaced apart cross-members and welded at its side edges to the depressed marginal edge portions of the web portions, the thickness of said plate members being substantially equal to the amount by which the marginal side edge portion of a web portion is depressed, said side rails each including a vertical wall, the end edges of said plate members of said web members and of the depending walls of the web portion abutting the vertical wall and being welded thereto, to secure said plate members, cross-members and side rails together into a unitary selfcontained structure free of external fastening devices and/or overlapping portions of materials.
 2. In a portable cargo carrying container according to claim 1 wherein the depending wall of at least one side rail is provided centrally of its ends with at least one pair of longitudinally spaced openings for receiving the lifting forks of a freight-handling vehicle, each opening registering with the space between a pair of adjacent cross-members beneath an intervening plate member.
 3. In a portable cargo carrying container according to claim 2 wherein the depending walls from each cross-member terminates at their free ends with inwardly turned flanges extending toward one another.
 4. In a portable cargo carrying container according to claim 1 wherein the depending walls from each cross-member terminates at their free end with inwardly turned flanges extending toward one another.
 5. In a portable cargo carrying container according to claim 1 wherein the plate members and web portions are provided with transversely extending evenly spaced stiffening indentations along the lengths thereof.
 6. In a portable cargo carrying container according to claim 1 wherein the plate members and web portions are provided with transversely extending evenly spaced stiffening indentations along the lengths thereof. 